Years ago when I was playing object golf we had several mandos on our course at Southern MS and we played that you had to pass the mando. If you missed you had to go back and pass it correctly. As per the rules listed earlier it is generally a 1 stroke penalty. The only problem I have found is that for casual play the drop zone is often not clear or nonexistent. In casual play the best idea is to talk with your group before playing the hole and decide how you are going to play the mando.

A. A mandatory restricts the path the disc may take to the target. A disc must pass to the correct side of the mandatory before the hole is completed. Once the disc has completely passed the mandatory line on the correct side (even if it subsequently re-crosses the line), the mandatory is to be ignored for the remainder of play on that hole.

(1) The mandatory line is the line marked by the director or course designer to indicate when a disc has passed or missed the mandatory.

(2) If no line is marked, the mandatory line is defined as a straight line through the mandatory, perpendicular to the line from the tee to the mandatory.

(3) In the case of a double mandatory when no line is marked, the mandatory line is the straight line connecting the two mandatories, and extends beyond them in both directions.

B. A throw is considered to have missed the mandatory if it passes the incorrect side of the mandatory line from the direction of the tee, and comes to rest lying completely beyond that line.

C. A disc that has missed the mandatory results in a one-throw penalty and the next throw shall be made from the drop zone, as designated for that mandatory. In cases where the drop zone is not designated, the lie is marked within five meters of the mandatory object and one meter behind the mandatory line which extends from the correct side of the mandatory.

D. When marking the lie, if the line of play does not pass to the correct side of the mandatory, then the mandatory itself shall be considered the hole for the application of all rules regarding stance, markers, obstacles, and relief. For the purposes of taking a legal stance, the mandatory object which has not yet been passed, and is nearest the tee, will be considered to be the hole.

E. A throw that misses a mandatory shall be penalized and the lie marked according to the mandatory rule (803.12). It will not be further penalized for any other reason, such as out-of-bounds or above two meters.

you either shoot from where it landed and take 1 stroke or re-tee and take two.

(which doesn't make any sense, i know)

i'm sure the first scenario wouldn't float in a tourney, but like i said, it's casual play

If it doesn't make sense (which it doesn't), then why do you play that way? Playing from where your disc landed if it didn't meet the mando completely defeats the purpose of the mando, even with a stroke penalty. If you were going to play that way, I would think you should do 2 stroke penalty from where it landed and 1 stroke for the re-tee.

God I hate mandos!!! You should be able to throw from the tee to the basket anyway you choose!

Usually a mando is there for one of two reasons: safety issues or to add challenge to an otherwise easy hole. I have no problem with safety issue mandos, but a hole that's too easy without a forced line is a design problem that should be thought about a little harder.

That said, I do like the roped off islands around the pin on short holes though.

This mando is for safety, because the straight line path goes right through the next tee pad. Luckily there was noone playing in front of us that day, and I only missed the mando by the width of the tree.

Usually a mando is there for one of two reasons: safety issues or to add challenge to an otherwise easy hole. I have no problem with safety issue mandos, but a hole that's too easy without a forced line is a design problem that should be thought about a little harder.

That said, I do like the roped off islands around the pin on short holes though.

I just played in a tournament this past weekend and there was a mando to prevent people from throwing over a basketball court due to other park users. There was also another one on a short hole to make it a little more difficult. (both had drop zones if they were missed with a 1 stroke penalty)

We have always played it as, throw from your spot back around the mando.

But because of this great thread, we will start:
C. A disc that has missed the mandatory results in a one-throw penalty and the next throw shall be made from the drop zone, as designated for that mandatory. In cases where the drop zone is not designated, the lie is marked within five meters of the mandatory object and one meter behind the mandatory line which extends from the correct side of the mandatory.